An app requires adding a hard-copy capability. Think of a "batch ticket" that gives date/time/amount/moon phase/etc.
AVR has an available USART port, that we can turn into RS232 or RS485 or ...
We did find one RS232-to-USB adapter that we are going to try, that claims to be for this task. ("cheap" printers seem to be USB...)
Yeah, the cheap printers often have wireless but I think I'd try to avoid it in this particular industrial environment.
So I get a cheap printer -- what commands do I send it? Do I need to develop a "driver"?
LOL -- 15+ years of doing AVR8 apps, and the first time for hard-copy. All others send e.g. log files to a PC and then reports from there.
A first look at cheap printers leads us to small laser (to avoid inkjet mess/smearing). But perhaps some POS terminal printer would work as well -- probably don't need a full page.